Pat test on Battery Charger.

[Rocky1964]

Morning all.
I have a battery charger for a 9V drill.
It's double insulated and i'm treating it as IT because of the electronics inside.
I believe the only test I can carry out is the Leakage test (which is satisfactory at <0.1mA)
I'm new to pat testing but thought I'd got it sussed!
I've checked copies of test results for various companies and they all state the insulation resistance in m ohms.
How can thy be carrying out insulation tests on this type of equipment?

Cheers,

Dave

 

[telectrix]

Morning all.
I have a battery charger for a 9V drill.
It's double insulated and i'm treating it as IT because of the electronics inside.
I believe the only test I can carry out is the Leakage test (which is satisfactory at <0.1mA)
I'm new to pat testing but thought I'd got it sussed!
I've checked copies of test results for various companies and they all state the insulation resistance in m ohms. M ohms
How can thy be carrying out insulation tests on this type of equipment? they can't.

 

[Rocky1964]

Thanks for the speedy response!
Not being funny but I've been a spark for over 30 years! I didn't realise I was going to get corrected for incorrect punctuation!
I think I was at school the last time I had something corrected in red!!!
I bow to your superior intelligence and will remember to put my glasses on the next time I post something!
GEEZE!

 

[DPG]

I don't think it was punctuation that was the problem - it was the fact that used milli instead of Mega prefix. Daz

 

[Lucien Nunes]

I believe the only test I can carry out is the Leakage test (which is satisfactory at <0.1mA)

If you can do a leakage test on double-insulated equipment, that implies you've got somewhere to connect your touch-leakage probe. If so, you can do an insulation test. If not (e.g. something that is entirely plastic) then what is your leakage test actually testing?

With isolated battery chargers, such as car battery chargers where you can touch the ELV output, you can and should test to an output terminal both for insulation and leakage, as isolation is needed between primary and secondary sides. Many but not all cordless tool chargers are non-isolated and the battery is part of the 230V circuit while on charge. These will have touchproof battery terminals and usually a voltage hazard sign nearby. Obviously do not test to these as you will short-circuit the charger electronics.

BTW that is why there are usually stern warnings about not using broken battery packs as the cells are live with 230V when on charge, which most people don't realise.

Also, I would not call a tool charger 'IT equipment'. It can withstand being powered up/down repeatedly and has no signal-level interconnects, so it does not require special treatment. Indeed I routinely apply full 25A and 500V tests to IT equipment too but care and knowledge are needed to ensure things don't get fried.

 

[DPG]

It's amazing how many people PAT test appliances like this (eg. all plastic) and give a pass for earth tests. Same for people testing figure 8 mains leads - 'well the tester says PAS so it must be OK'. The trouble is many tests will give a pass result when nothing is connected! (for obvious reasons). Daz